The present invention relates to a method of establishing an Internet Protocol (xe2x80x9cIPxe2x80x9d) network with several IP hosts and with an IP gateway for connecting the IP network to the internet.
Explanation of the concepts used in conjunction with the invention:
Several possibilities are known from the state of the art for establishing an IP network:
The user manually allocates an IP address and an IP network mask to each IP host in the IP network. Each additional IP host which is to be tied into the IP network therefore requires an additional establishing cost. The working cost includes the fact that the user must know and have understood the address mechanisms of the Internet protocol since an erroneous establishment of individual IP hosts can absolutely result in a disturbance in the entire IP network. If the user desires to connect the IP network to the Internet he requires an IP gateway for this whose IP address must also be entered manually in each IP host of the IP network. Usually, additional IP addresses are entered into each IP host, converted into symbolic names, e.g., for the Domain Name Service (DNS in short) of the IP addresses and vice versa. The Domain Name Service is practically indispensable when working in the Internet.
Another possibility for a new establishment of an IP network is that the user allocates an IP address and an IP network mask to only one IP host and uses this IP host for allocating IP addresses and IP network masks to additional IP hosts in the IP network. This is carried out by means of DHCP (DHCP: Abbreviation for Dynamic Host Configuration Protocol), which must be installed in the host. The DHCP is defined via RFC 2131 and RFC 2132 (See the explanations for xe2x80x3xe2x80x9cRFCxe2x80x9d). The IP host established manually by the user functions as DHCP server for the additional IP hosts, the DHCP clients. The allocation of the IP addresses to the IP hosts functioning as DHCP clients takes place from the DHCP server, in which the user transfers IP addresses left on the DHCP server from the latter to the DHCP clients=IP hosts. This applies to the IP addresses of the IP hosts as well as to additional IP addresses, e.g., of a DNS server. The connection of the IP gateway to the IP network nevertheless requires a manual establishment since the IP gateway can not be established from a DHCP server. Even in this method of establishing an IP network the user must know and have understood the address mechanism of the Internet protocol. Only the establishing cost for the IP hosts is eliminated.
Therefore, a central disadvantage of the known methods is the fact that the user must know and have understood the address mechanisms of the Internet protocol for a successful establishment of the IP network. Any errors in the establishment can absolutely result in a disturbance in the entire IP network. The known methods are therefore not suited for users without considerable knowledge of the Internet protocol.
The invention therefore has the basic problem of creating a method of establishing an IP network with several IP hosts and with an IP gateway which method requires no knowledge of the address mechanisms of the Internet protocol for a successful establishment and therewith protects against disturbances, resulting from errors during the establishing.
The solution of this problem makes use of the fact that all information necessary for establishing an IP network with Internet connection converge in the IP gateway.
The invention is also based on the concept, contrary to the traditional method, of at first not using a DHCP server for the establishment but rather of allowing the IP gateway to find out in the non-established state as DHCP client whether there is a DHCP server in the IP network already. If there is no DHCP server the IP gateway is activated automatically as DHCP server. The software (IP stack) for this is implemented in the firmware of the gateway so that the user is not burdened with the installation. The activated DHCP server allocates IP addresses and IP network masks to the IP hosts in a standard manner from a reserved address range so that the IP hosts and the IP gateway can exchange IP data packets with each other. Exclusively IP addresses which) are not given out in the Internet for IP hosts are normally located in the reserved address range.
The problem is solved by the present invention.
However, If the IP gateway discovers as DHCP client that there is a DHCP server in the IP network already the IP gateway does not activate its own DHCP server and logs off again in the found DHCP server because an establishment and administration of the IP network in a traditional way with an IP host as DHCP server is obviously intended.